1. Field of the Invention
The present invention relates to a swage mount plate that is used to attach a suspension arm to an actuator arm of a hard disk drive.
2. Background Information
Hard disk drives contain a plurality of heads that are magnetically coupled to the surfaces of magnetic disks which are rotated by a spindle motor. Each head typically includes a write element that can magnetize the disk surface and a read element that can sense the magnetic field of the disk surface. Binary information can be stored and retrieved from the disks by magnetizing and sensing the magnetic fields of the disk surfaces as is known in the art.
Each head typically has an air bearing surface which cooperates with an air flow created by the rotating disks to create an air bearing between the head and the surface of the disk. The air bearing prevents mechanical wear between the head and the disk. It is desirable to minimize the height of the air bearing to maximize the magnetic coupling between the read/write elements and the disks.
When the disk drive is powered down the disks are spun down and the heads land on the disk surfaces. When the disk drive is powered up the disks are again rotated to generate an air flow which creates the air bearings between the heads and the disk surfaces. The creation of the air bearings moves the heads away from the disk surfaces. To allow this movement the heads are typically mounted to a suspension arm which is flexible to become deflected under the force of the air bearing. A head and suspension arm are commonly referred to as a head gimbal assembly (HGA).
The suspension arm is attached to an actuator arm that is pivotally mounted to a base plate of the disk drive. The actuator arm has a voice coil which is coupled to a magnet assembly. The voice coil and magnet assembly are commonly referred to as a voice coil motor (VCM). The voice coil motor can be excited by an electrical circuit(s) to induce a pivotal movement of the actuator arm relative to the base plate. Pivoting the actuator arm moves the heads across the surfaces of the disks. Data is typically stored within annular tracks of the disks. The voice coil motor allows the heads to access the different tracks of the disks.
Each suspension arm is typically attached to a corresponding actuator beam of the actuator arm with a swage mount plate. The swage mount plate has a sleeve that extends through openings in both the suspension arm and the actuator beam. A swage ball is pushed through an inner sleeve opening to expand the sleeves into the actuator beam. The swage plate may have a lip that captures the suspension arm to attach the arm to the actuator beam. The retention force of the swage plate is proportional to the surface area of the sleeve.
It is generally desirable to assemble more disks into a disk drive while minimizing the height of the drive. These criteria may require a reduction in the thickness of the actuator beams and the height of the swage plate sleeves. A shorter sleeve may reduce the retention torque of the swage plate. It would be desirable to provide a swage mount plate which has a higher retention torque per sleeve height than plates of the prior art.
One embodiment of the present invention is a swage mount plate that can be used to attach a suspension arm to an actuator beam of a hard disk drive. The swage mount plate may include a sleeve that can be inserted into corresponding swage openings of the suspension arm and the actuator beam. The swage plate may include at least one flange that extends from said sleeve.